Zoonotic Diseases (Diseases spread between animals and people)

Zoonotic Diseases are disease shared by humans and animals. The transfer of disease from an animal to a human can either be by direct contact with the animal, from the animals secretions (nasal discharge, saliva etc), or excretions (stool or urine), or contact with vehicles of transmission such as water, food, or parasites (like fleas) that were contaminated by an animal.

Important Zoonotic Diseases in Minnesota

Disease

Transmission

Clinical Signs in Animals

Clinical Signs in People

More Information

The Tapeworm Dipylidium caninum

Accidental ingestion of an infected flea.

Sometimes no symptoms, but can cause abdominal pain, diarrhea and anal itchiness.

Sometimes no symptoms, but can cause abdominal pain, diarrhea and anal itchiness.

Roundworm eggs are spread in feces. It takes 3-4 weeks for the eggs to become infectious. Stool that is not removed from the environment can lead to environmental contamination. Human exposure can occur through accidental ingestion of contaminated soil (gardening without gloves, or eating fresh, unwashed fruits or vegetables). Dogs and cats can also get roundworms from eating prey and from their mother's milk. Pregnant dogs can also spread it to their puppies through the placenta.

Diarrhea is the most common symptom. However, roundworm larvae can migrate through internal organs and cause disease. Coughing is a common symptom seen if larvae are traveling through the lungs.

The two syndromes seen in humans are: Visceral larva migrans (VLM) and Ocular larva migrans (OLM). Roundworm larvae can travel through internal organs and the eyes, causing inflammation and disease.

Hookworms eggs are spread in feces. It takes 2-9 days for eggs to turn into infective larvae. Humans can get infected either through accidental ingestion of contaminated soil, or the larvae may penetrate the skin, like when walking barefoot in a contaminated area. Cats and dogs can also be infected this way as well as eating prey or cockroaches carrying hookworm. Dogs may also spread hookworms to their puppies through milk.

Hookworms are voracious blood suckers in the intestinal tract, so a common sign of hookworms in dogs and cats is anemia. Hookworms are particularily dangerous to young puppies who can get infected while nursing. Diarrhea can also occur, as well as

symptoms related to traveling larvae, particularily coughing when traveling through the lungs.

The most common symptom in affected humans is sores from larval migration through the skin.

"Crypto" is spread in feces and is immediately infectious. Although people can get "Crypto" directly from their dog or cat, the most common source of infection for humans is through contaminated water or from livestock.

Cats and dogs don't always show symptoms, but in young, old, or immunosuppressed animals, gastrointestinal problems like diarrhea can occur.

Cats are the definitive host of this organism and the only animal known to shed the oocyst in their stool. It takes 24 hours for the oocyst to become infective. Removing feces from the litterbox daily is an important method of controlling spread of this disease. Although cats can spread toxoplasma to humans, they are not the most common source of infection, eating undercooked meat is. Other possible sources of infection are raw milk (particularily goat's milk) and accidental ingestion of contaminated soil.

Symptoms can range from mild to severe. Mild symptoms usually go unnoticed. Severe symptoms can include fever, swollen lymph nodes, muscle or joint pain and liver or spleen swelling. Cats can also develop diarrhea during the intestinal phase of their infection.

Symptoms can range from mild to severe. Mild symptoms usually go unnoticed and can sometimes be dismissed as a bad cold. Severe symptoms can include fever, swollen lymph nodes, muscle or joint pain and liver or spleen swelling and are often diagnosed as mononucleosis. If a pregnant woman is exposed to the toxoplasma organism, it may cross through the placenta and effect the fetus. The degree of damage depends on the stage of pregnancy at the time of infection. Complications can range from miscarriage to blindness in the infant. Pregnant women are encouraged to discuss toxoplasmosis with their healthcare provider.

This bacteria is spread through feces. Although humans can get salmonella from a dog or cat, most sources of human infection is through exposure to undercooked meats. Cross contamination or transmission between foods by flies can also occur.

Dogs or cats can have salmonella bacteria in their intestinal tract and not show symptoms. If they do develop illness from the bacteria, vomiting and diarrhea are the common signs. An important disease in cats is called "Songbird Fever". Cats (or dogs) can get sick from eating a bird or bird droppings that contain salmonella.

Cats have a variety of bacteria in their mouth that can cause serious infections.

Sometimes a bite wound isn't noticed immediately because fur can cover it up. After several days however, the cat (or dog) that has been in a fight with a cat can develop an abscess, fever, and sometimes lameness if the bite was on a limb.

When humans get bit by a cat, the bite can have very serious consequences. Local infection can occur, but also the bacteria can spread through the body causing meningitis, endocarditis, septic arthritis, septic shock and death.

There are two ways that rabies can present in animals. The Furious form, the animial becomes aggressive and begins to attack other animals. In the Dumb form, the animal becomes lethargic.

Initially the symptoms can mimic the flu. As the disease spreads to the brain, the patient can experience delirium, abnormal behavior and hallucinations. Once symptoms of rabies have appeared, the disease is almost always fatal. Having your pet cat, dog, ferret and horse vaccinated for rabies will help protect you and your family from rabies as animals are more likely to encounter wildlife then humans are.

The most common mode of transmission to both animals and humans is through ticks. However, contact with infected animals (like rabbits, rodents and cats), and exposure to contaminated water and soil can also occur. Cats and dogs can get the disease from eating infected rabbits and rodents.

Humans have their own version of Chlamydia (C. trachomatis) which is a venereal disease.

The cat version of Chlamydia (C. felis), causes severe conjunctivitis and respiratory problems.

There have been a couple of documented cases of humans developing disease from C. felis. Pneumonia was documented in 1 man. A cough was documented in 1 immunosuppressed woman, and there is another report of a woman developing endocarditis and glomerulonephritis from C. felis.

Humans can get ringworm from direct contact with a contaminated animals, or from the environment. The spores from ringworm are very hardy and can live in the environemnt for years. They do not cause infection on healthy skin, but if the person is very young, old, immunocompromised or if the skin has been damaged, a ringworm infection can occur.

Hairloss, crusts and scales on the skin. Cats can also be subclinical carriers.

The bacteria that cause leptospirosis are spread through the urine of infected animals, which can get into water or soil and can survive there for weeks to months. Humans and animals can become infected through contact with this contaminated urine (or other body fluids, except saliva), water, or soil.

Leptospirosis can cause liver and kidney failure. Signs of organ dysfunction can include vomiting, diarrhea, poor appetite, lethargy and fever.

Humans are the natural host. Group A strep is the principle cause of “strep throat” It is theoretically possible that a cat or dog in close contract with infected humans could develop colonization of pharyngeal tissues which could lead to infection in the animal which could then be spread back to humans. However, this is poorly documents and is unlikely.

Occasionally veterinarians are asked to performa throat culture on a cat or dog. There are some other normal strep inhabitants of the oral cavity of cats and dogs so Group A Strep must be specifically looked for.

Commonly called "kennel cough" in dogs. This bacteria can cause a loud, honking cough. Cats can also develop upper respiratory infections from B. bronchiseptica, but often they have no symptoms of disease.

Although rare, the organism can also cause respiratory problems in people. By 1998, 39 cases of B. bronchispetica infection in humans had been reported, many of the humans were innumodeficient.

We think that Helicobacter can be spread through vomit and feces, although we are not sure if it can be spread between animals and humans. There is one documented case of a man with helicobacter, who’s cat had a genetically identical helicobacter. (It was h. heilmanni, not the h. pylori that typically causes ulcers in humans).

H. pylori has been found in cats, but the most common helicobacter species in cats is H. heilmanni, and in dogs it is H. bizzozeronii.

In humans, H. pyloria has been linked stomach ulcers and stomach cancer.

Animals should be examined by a veterinarian before being brought into the home. They should be quarantined from immunosuppressed individuals until determined by a veterinarian to be free of contagious disease.

Seek veterinary care for an unhealthy cat or dog.

All cats and dogs should be vaccinated for rabies.

Avoid handling unhealthy cats or dogs.

Avoid handling cats or dogs you are unfamiliar with.

Do not allow animals to drink from the toilet.

Wash hands after handling animals.

Periodically clean litterboxes with scalding water and detergent. Clean fecal material out of the environment daily. When possible do not have an immunosuppressed individual clean up feces.

Wear gloves when gardening and wash hands thoroughly when finished.

Cover sandboxes to avoid fecal contamination by outdoor cats.

Only feed cooked or commercially processed food to your cat or dog. (Do not feed a raw diet)

Control parasites such as fleas, ticks, and cockroaches.

Housing cats indoors can reduce their exposure to other animals and their excrement which may carry contagious disease.

Do not share food utensils with your animals.

Avoid having your cat or dog lick your face.

Have your cat’s claws trimmed to avoid scratches.

If bitten or scratched by your cat or dog, seek medical attention.

Wear gloves when handling meat and wash hands thoroughly with soap and water when finished.